﻿using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Security.Cryptography;
using System.Text;

namespace JinKaiBodyCheck.Common.Helper
{
    public static class WXApi
    {
        /// <summary>
        /// 过期时间
        /// </summary>
        public static DateTime OutDateTime { get; set; }
        /// <summary>
        /// 凭据
        /// </summary>
        public static string Token { get; set; }
        /// <summary>
        /// 船票
        /// </summary>
        public static string Ticket { get; set; }
        /// <summary>
        /// 获取微信api接口船票
        /// </summary>
        /// <param name="url">请求页面地址</param>
        /// <param name="appId">开发者Id</param>
        /// <param name="secret">开发者密码</param>
        /// <returns></returns>
        public static dynamic GetConfig(string url, string appId, string secret)
        {
            var timestamp = CreatenTimestamp();
            var noncestr = CreatenNonce_str();
            var ticket = Ticket;
            if (DateTime.Now > OutDateTime)
            {
                var token = GetToken(appId, secret);
                if (!string.IsNullOrEmpty(token))
                {
                    OutDateTime = DateTime.Now.AddMinutes(90);
                    Token = token;
                    Ticket = GetTickect(Token);
                    ticket = Ticket;
                }
            }
            var signature = GetSignature(ticket, noncestr, timestamp, url, out var str);
            return new
            {
                ticket,
                appId,
                url,
                timestamp,
                noncestr,
                signature,
                str
            };
        }
        /// <summary>
        /// 获取凭据
        /// </summary>
        /// <param name="appid"></param>
        /// <param name="secret"></param>
        /// <returns></returns>
        public static string GetToken(string appid, string secret)
        {
            var url = string.Format("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={0}&secret={1}", appid, secret);
            var client = new HttpClient();
            var result = client.GetAsync(url).Result;
            if (!result.IsSuccessStatusCode) return string.Empty;
            var jsTicket = result.Content.ReadAsStringAsync().Result;
            var v = JsonConvert.DeserializeObject<dynamic>(jsTicket);
            return v.access_token.ToString();
        }
        /// <summary>
        /// 获取船票
        /// </summary>
        /// <param name="token"></param>
        /// <returns></returns>
        public static string GetTickect(string token)
        {
            var url = string.Format("https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token={0}&type=jsapi", token);
            var client = new HttpClient();
            var result = client.GetAsync(url).Result;
            if (!result.IsSuccessStatusCode) return string.Empty;
            var jsTicket = result.Content.ReadAsStringAsync().Result;
            var v = JsonConvert.DeserializeObject<dynamic>(jsTicket);
            return v.ticket.ToString();
        }
        /// <summary>
        /// 获取时间戳
        /// </summary>
        /// <returns></returns>
        public static long CreatenTimestamp()
        {
            return (DateTime.Now.ToUniversalTime().Ticks - 621355968000000000) / 10000000;
        }

        ///  <summary>
        ///  签名算法
        /// 本代码来自开源微信SDK项目：https://github.com/night-king/weixinSDK
        ///  </summary>
        ///  <param name="jsapi_ticket">jsapi_ticket</param>
        ///  <param name="noncestr">随机字符串(必须与wx.config中的nonceStr相同)</param>
        ///  <param name="timestamp">时间戳(必须与wx.config中的timestamp相同)</param>
        ///  <param name="url">当前网页的URL，不包含#及其后面部分(必须是调用JS接口页面的完整URL)</param>
        /// <param name="string1"></param>
        /// <returns></returns>
        public static string GetSignature(string jsapi_ticket, string noncestr, long timestamp, string url, out string string1)
        {
            url = url.Split('#')[0];
            var string1Builder = new StringBuilder();
            string1Builder.Append("jsapi_ticket=").Append(jsapi_ticket).Append("&")
                .Append("noncestr=").Append(noncestr).Append("&")
                .Append("timestamp=").Append(timestamp).Append("&")
                .Append("url=").Append(url);
            string1 = string1Builder.ToString();
            return Sha1(string1);
        }
        /// <summary>
        /// 创建随机字符串
        ///本代码来自开源微信SDK项目：https://github.com/night-king/weixinSDK
        /// </summary>
        /// <returns></returns>
        public static string CreatenNonce_str()
        {
            var strs = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray();
            Random r = new Random();
            var sb = new StringBuilder();
            var length = strs.Length;
            for (int i = 0; i < 15; i++)
            {
                sb.Append(strs[r.Next(length - 1)]);
            }
            return sb.ToString();
        }
        /// <summary>
        /// HMAC-SHA1加密算法
        /// </summary>
        /// <param name="str">加密字符串</param>
        /// <returns></returns>
        public static string Sha1(string str)
        {
            var sha1 = SHA1.Create();
            var hash = sha1.ComputeHash(Encoding.UTF8.GetBytes(str));
            string byte2String = string.Empty;
            foreach (var t in hash)
            {
                byte2String += t.ToString("x2");
            }
            return byte2String;
        }
    }
}
